Machines such as, for example, haul trucks, drills, loaders, conveyors, and other types of heavy equipment are commonly used in underground mining applications to perform a variety of tasks. Some of these tasks involve carrying or pushing material through long tunnels that have environmental conditions that vary along their lengths. These environmental conditions can include, among other things, a low quality or low supply rate of air found at mid-portions of the tunnels. When passing through these tunnels, care should be taken such that the conditions at the mid-portions do not cause machine malfunctions or create situations unsuitable for prolonged human occupation. One precaution currently implemented includes manually reducing machine performance in certain tunnel sections such that the environmental conditions in those sections do not degrade below acceptable levels. Another precaution includes banning certain machines from particular tunnel sections. Both of these precautions are undesirable, however, as they tend to increase operator responsibility, generate opportunities for error, and lower productivity. Accordingly, another way to account for varying environmental conditions in particular work zones is desired.
U.S. Patent Publication No. 2009/0160604 (the '604 publication) of Nguyen that published on Jun. 25, 2009 describes a vehicle speed control system that automatically affects vehicle operation based on a vehicle location relative to a designated speed control zone. Specifically, the '604 publication describes a system that includes a computer for controlling operating functions of a vehicle when RFID tags onboard the vehicle are sensed by an offboard station positioned adjacent the designated speed control zone. The offboard station is capable of sending a speed control command to the vehicle as the vehicle passes through the speed control zone, thereby causing components of the vehicle to automatically reduce the speed of the vehicle. The components reduce the speed of the vehicle by reducing vehicle fueling.
Although the system of the '604 publication may automatically reduce vehicle speed in a designated control zone, the speed reduction may have an insignificant effect on air consumption or quality within the zone. In addition, by controlling only vehicle fueling, inefficiencies may be realized. Further, the system of the '604 publication may only function in zones equipped with the offboard station, which can be limiting and expensive.
The disclosed control system is directed to overcoming one or more of the problems set forth above and/or other problems of the prior art.